Various sports require the use of balls and backstops therefor, such as nets placed behind the catcher in baseball, or practice nets into which balls are directed or thrown. For example, the game of tennis is practiced by serving and/or returning served balls into a net that damps the trajectory of and arrests the balls so that retrieval is not a problem. And, ball nets of this description must be rather extensive in order to be practical, and all of which necessitates the erection of supporting standards such as poles and frames. The permanency of fixed installations is a great disadvantage, and for this reason portable frames for the support of ball arresting nets have been proposed but which tend to be complicated, ungainly and met with erection and dismantling difficulties. Further, such frames tend to be flimsy with bracing for rigidity rather than utilizing the functions of flexibility to advantage which is an object of this invention.
Height expansion of such frames most often requires the use of auxiliary equipment such as chairs and/or ladders for installing and/or removing the net, it being an object herein to provide a self-sufficient ball net frame. Portability is a primary object of this invention, to provide ball net frame that can be carried within a minimum of space and erected and/or collapsed without the use of any auxiliary equipment. Further, it is an object to provide for augmentation of the frame size as circumstances require to accommodate nets of different size. With this invention, there are telescoped tubular members which fold together into a compact bundle when collapsed, with parts and members remaining interconnected and available for extension without any rearrangement thereof. Augmentation of the frame is determined by the height and width requirements of the net to be suspended thereby, and the weight and balance of the erected members inherently suspends a net for the absorption of energy in arresting a ball impacting into the net, whether the impact point be at the margin thereof or centered therein.
The simple and rugged character of this frame is an object wherein mass and placement of the center of gravity is a factor that operates in conjunction with flexibility and collapsibility as well, to absorb ball energy without damage to the structure. With the present invention, the impact forces of a ball impinging into the net causes frame movements in a direction of collapse thereof, but without adverse affect while remaining erected in ground engaged equilibrium. That is, the frame is massive with a center of gravity that makes it stable, not only to support the static weight of the net but also to remain stable against the dynamic forces applied in arresting the motion of a ball. In practice, the ball net tends to pull together along its margins upon ball impact, and to this end the frame is flexible so as to permit shortening of the top margin of the net, and as well to permit some rearward swing of the frame members that are flexible as well; the net being held taut between said frame members in readiness for the impact of balls therewith.
It is an object to provide a ball net frame of compact and simple construction, and such a frame that is expansively adjustable. To this end, there are base and standard members that are telescoping with stops for both extended and collapsed conditioning, and with adjustment for both height and width of the nets to be used therewith. In practice, there is an A-frame base wherein each leg carries a standard, the base legs being adjustable in angular displacement to carry the extensible standards that suspend the net. The spread of the base is essentially rigid while support of the standards thereby is resilient, the standard being flexibly resilient as well.